diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2018-06-28 15:53:17 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2018-08-03 15:55:30 -0400 |
| commit | c2b6d621c4ffe9936adf7a55c8b1c769672c306f (patch) | |
| tree | d13dbb52a33dd594a78b8996132c7e7bba6f296f /include/linux/fs.h | |
| parent | c971e6a006175bd0f195c6346c4e8bc4089bec00 (diff) | |
new primitive: discard_new_inode()
We don't want open-by-handle picking half-set-up in-core
struct inode from e.g. mkdir() having failed halfway through.
In other words, we don't want such inodes returned by iget_locked()
on their way to extinction. However, we can't just have them
unhashed - otherwise open-by-handle immediately *after* that would've
ended up creating a new in-core inode over the on-disk one that
is in process of being freed right under us.
Solution: new flag (I_CREATING) set by insert_inode_locked() and
removed by unlock_new_inode() and a new primitive (discard_new_inode())
to be used by such halfway-through-setup failure exits instead of
unlock_new_inode() / iput() combinations. That primitive unlocks new
inode, but leaves I_CREATING in place.
iget_locked() treats finding an I_CREATING inode as failure
(-ESTALE, once we sort out the error propagation).
insert_inode_locked() treats the same as instant -EBUSY.
ilookup() treats those as icache miss.
[Fix by Dan Carpenter <dan.carpenter@oracle.com> folded in]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/fs.h')
| -rw-r--r-- | include/linux/fs.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 5c91108846db..a42600565925 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2016,6 +2016,8 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) * I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper * and work dirs among overlayfs mounts. * + * I_CREATING New object's inode in the middle of setting up. + * * Q: What is the difference between I_WILL_FREE and I_FREEING? */ #define I_DIRTY_SYNC (1 << 0) @@ -2036,7 +2038,8 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) #define __I_DIRTY_TIME_EXPIRED 12 #define I_DIRTY_TIME_EXPIRED (1 << __I_DIRTY_TIME_EXPIRED) #define I_WB_SWITCH (1 << 13) -#define I_OVL_INUSE (1 << 14) +#define I_OVL_INUSE (1 << 14) +#define I_CREATING (1 << 15) #define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC) #define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES) @@ -2919,6 +2922,7 @@ extern void lockdep_annotate_inode_mutex_key(struct inode *inode); static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { }; #endif extern void unlock_new_inode(struct inode *); +extern void discard_new_inode(struct inode *); extern unsigned int get_next_ino(void); extern void evict_inodes(struct super_block *sb); |